Add basic type checking for native type declarations

11 files changed, 323 insertions, 4 deletions

diff --git a/src/main/java/org/shedlang/compiler/ast/typed/TypedNamespaceStatementNode.java b/src/main/java/org/shedlang/compiler/ast/typed/TypedNamespaceStatementNode.java
index d38cff5e..c63b58d7 100644
--- a/src/main/java/org/shedlang/compiler/ast/typed/TypedNamespaceStatementNode.java
+++ b/src/main/java/org/shedlang/compiler/ast/typed/TypedNamespaceStatementNode.java
@@ -1,4 +1,4 @@
 package org.shedlang.compiler.ast.typed;
 
-public sealed interface TypedNamespaceStatementNode extends TypedNode permits TypedAssignNode, TypedEffectDefinitionNode, TypedFunctionDefinitionNode, TypedNativeFunctionDeclarationNode, TypedStructDefinitionNode, TypedSumTypeDefinitionNode {
+public sealed interface TypedNamespaceStatementNode extends TypedNode permits TypedAssignNode, TypedEffectDefinitionNode, TypedFunctionDefinitionNode, TypedNativeFunctionDeclarationNode, TypedNativeTypeDeclarationNode, TypedStructDefinitionNode, TypedSumTypeDefinitionNode {
 }
diff --git a/src/main/java/org/shedlang/compiler/ast/typed/TypedNativeTypeDeclarationNode.java b/src/main/java/org/shedlang/compiler/ast/typed/TypedNativeTypeDeclarationNode.java
new file mode 100644
index 00000000..2c438577
--- /dev/null
+++ b/src/main/java/org/shedlang/compiler/ast/typed/TypedNativeTypeDeclarationNode.java
@@ -0,0 +1,50 @@
+package org.shedlang.compiler.ast.typed;
+
+import org.pcollections.PVector;
+import org.shedlang.compiler.sources.Source;
+import org.shedlang.compiler.sources.Sources;
+import org.shedlang.compiler.types.*;
+import org.shedlang.compiler.util.P;
+
+import java.util.List;
+
+public record TypedNativeTypeDeclarationNode(
+    TypeOrConstructor<SimpleNativeType> typeOrConstructor,
+    List<TypedNativeFunctionDeclarationNode> methods,
+    Source source
+) implements TypedNamespaceStatementNode {
+    public static Builder builder() {
+        var namespaceName = NamespaceName.of("Default", "Test", "Namespace");
+        return new Builder(
+            TypeOrConstructor.type(Types.nativeType(namespaceName, "X")),
+            P.vector()
+        );
+    }
+
+    public record Builder(
+        TypeOrConstructor<SimpleNativeType> type,
+        PVector<TypedNativeFunctionDeclarationNode> methods
+    ) {
+        public TypedNativeTypeDeclarationNode build() {
+            return new TypedNativeTypeDeclarationNode(
+                this.type,
+                this.methods,
+                Sources.NULL
+            );
+        }
+
+        public Builder withType(SimpleNativeType type) {
+            return new Builder(
+                TypeOrConstructor.type(type),
+                this.methods
+            );
+        }
+
+        public Builder addMethod(TypedNativeFunctionDeclarationNode method) {
+            return new Builder(
+                this.type,
+                this.methods.plus(method)
+            );
+        }
+    }
+}
diff --git a/src/main/java/org/shedlang/compiler/shid/ShidCodeGen.java b/src/main/java/org/shedlang/compiler/shid/ShidCodeGen.java
index bf6d2072..11827861 100644
--- a/src/main/java/org/shedlang/compiler/shid/ShidCodeGen.java
+++ b/src/main/java/org/shedlang/compiler/shid/ShidCodeGen.java
@@ -593,6 +593,9 @@ public class ShidCodeGen {
             case TypedNativeFunctionDeclarationNode nativeFunctionDeclaration ->
                 1;
 
+            case TypedNativeTypeDeclarationNode nativeTypeDeclaration ->
+                0;
+
             case TypedStructDefinitionNode structDefinition ->
                 0;
 
@@ -642,6 +645,9 @@ public class ShidCodeGen {
             case TypedNativeFunctionDeclarationNode nativeFunctionDeclaration ->
                 compileNativeFunctionDeclaration(nativeFunctionDeclaration, context);
 
+            case TypedNativeTypeDeclarationNode nativeTypeDeclarationNode ->
+                throw new UnsupportedOperationException("TODO");
+
             case TypedStructDefinitionNode structDefinition ->
                 compileStructDefinition(structDefinition, context);
 
diff --git a/src/main/java/org/shedlang/compiler/typechecker/TypeChecker.java b/src/main/java/org/shedlang/compiler/typechecker/TypeChecker.java
index 98fe892e..a9d98ff2 100644
--- a/src/main/java/org/shedlang/compiler/typechecker/TypeChecker.java
+++ b/src/main/java/org/shedlang/compiler/typechecker/TypeChecker.java
@@ -1609,7 +1609,7 @@ public class TypeChecker {
                 typeCheckStepsNativeFunctionDeclaration(nativeFunctionDeclaration);
 
             case UntypedNativeTypeDeclarationNode nativeTypeDeclaration ->
-                throw new UnsupportedOperationException("TODO");
+                typeCheckStepsNativeTypeDeclaration(nativeTypeDeclaration);
 
             case UntypedStructDefinitionNode structDefinition ->
                 typeCheckStepsStructDefinition(structDefinition);
@@ -1658,6 +1658,48 @@ public class TypeChecker {
         };
     }
 
+    private static TypeCheckSteps<TypedNativeTypeDeclarationNode> typeCheckStepsNativeTypeDeclaration(
+        UntypedNativeTypeDeclarationNode untyped
+    ) {
+        return new TypeCheckSteps<>() {
+            @Override
+            public TypeCheckerContext declareTypes(TypeCheckerContext context) {
+                var namespaceName = context.namespaceName()
+                    .orElseThrow(() -> new CannotDefineNativeTypeOutsideOfNamespaceError(untyped.source()));
+
+                var type = new SimpleNativeType(namespaceName, untyped.name());
+
+                var typeOrConstructor = createTypeOrConstructor(
+                    untyped.typeLevelParams(),
+                    type,
+                    new Scope.NativeType(type)
+                );
+
+                context = context.addLexicalState(untyped.name(), typeOrConstructor);
+
+                return context.declareVariableType(
+                    untyped.name(),
+                    typeOrConstructor.toMetaType(),
+                    untyped.source()
+                );
+            }
+
+            @Override
+            public TypeCheckerResult<TypedNativeTypeDeclarationNode> finish(TypeCheckerContext context) {
+                var typeOrConstructor = (TypeOrConstructor<SimpleNativeType>) context.getLexicalState(
+                    TypeOrConstructor.class,
+                    untyped.name()
+                );
+
+                return context.toResult(new TypedNativeTypeDeclarationNode(
+                    typeOrConstructor,
+                    List.of(),
+                    untyped.source()
+                ));
+            }
+        };
+    }
+
     private static TypedParamNode typeCheckParam(
         UntypedParamNode untyped,
         TypeCheckerContext context
diff --git a/src/main/java/org/shedlang/compiler/typechecker/errors/CannotDefineNativeTypeOutsideOfNamespaceError.java b/src/main/java/org/shedlang/compiler/typechecker/errors/CannotDefineNativeTypeOutsideOfNamespaceError.java
new file mode 100644
index 00000000..01e9dead
--- /dev/null
+++ b/src/main/java/org/shedlang/compiler/typechecker/errors/CannotDefineNativeTypeOutsideOfNamespaceError.java
@@ -0,0 +1,10 @@
+package org.shedlang.compiler.typechecker.errors;
+
+import org.shedlang.compiler.errors.InternalCompilerError;
+import org.shedlang.compiler.sources.Source;
+
+public class CannotDefineNativeTypeOutsideOfNamespaceError extends InternalCompilerError {
+    public CannotDefineNativeTypeOutsideOfNamespaceError(Source source) {
+        super("Cannot define native type outside of namespace", source);
+    }
+}
diff --git a/src/main/java/org/shedlang/compiler/types/Scope.java b/src/main/java/org/shedlang/compiler/types/Scope.java
index b0141916..9a61e51e 100644
--- a/src/main/java/org/shedlang/compiler/types/Scope.java
+++ b/src/main/java/org/shedlang/compiler/types/Scope.java
@@ -2,7 +2,7 @@ package org.shedlang.compiler.types;
 
 public sealed interface Scope {
     record Function(NamespaceName namespaceName, String name) implements Scope {}
-    record Native(NativeType type) implements Scope {}
+    record NativeType(org.shedlang.compiler.types.NativeType type) implements Scope {}
     record Struct(SimpleStructType type) implements Scope {}
     record Sum(SimpleSumType type) implements Scope {}
 }
diff --git a/src/main/java/org/shedlang/compiler/types/TypeParam.java b/src/main/java/org/shedlang/compiler/types/TypeParam.java
index 6d311940..c996dd97 100644
--- a/src/main/java/org/shedlang/compiler/types/TypeParam.java
+++ b/src/main/java/org/shedlang/compiler/types/TypeParam.java
@@ -10,7 +10,7 @@ public record TypeParam(Scope scope, String name) implements Type, TypeLevelPara
     }
 
     public static TypeParam forNativeType(SimpleNativeType nativeType, String name) {
-        return new TypeParam(new Scope.Native(nativeType), name);
+        return new TypeParam(new Scope.NativeType(nativeType), name);
     }
 
     public static TypeParam forStructType(SimpleStructType structType, String name) {
diff --git a/src/test/java/org/shedlang/compiler/ast/typed/TypedNativeTypeDeclarationNodeMatcher.java b/src/test/java/org/shedlang/compiler/ast/typed/TypedNativeTypeDeclarationNodeMatcher.java
new file mode 100644
index 00000000..16d3f36c
--- /dev/null
+++ b/src/test/java/org/shedlang/compiler/ast/typed/TypedNativeTypeDeclarationNodeMatcher.java
@@ -0,0 +1,62 @@
+package org.shedlang.compiler.ast.typed;
+
+import org.pcollections.PVector;
+import org.shedlang.compiler.testing.MatcherBuilder;
+import org.shedlang.compiler.types.SimpleNativeType;
+import org.shedlang.compiler.types.TypeConstructor;
+import org.shedlang.compiler.util.P;
+import org.zwobble.precisely.Matcher;
+
+import static org.shedlang.compiler.types.TypeMatchers.isConstructorNotType;
+import static org.shedlang.compiler.types.TypeMatchers.isTypeNotConstructor;
+import static org.zwobble.precisely.Matchers.has;
+
+public class TypedNativeTypeDeclarationNodeMatcher extends MatcherBuilder<
+    TypedNamespaceStatementNode,
+    TypedNativeTypeDeclarationNode,
+    TypedNativeTypeDeclarationNodeMatcher
+> {
+    public static TypedNativeTypeDeclarationNodeMatcher empty() {
+        return new TypedNativeTypeDeclarationNodeMatcher(P.vector());
+    }
+
+    private TypedNativeTypeDeclarationNodeMatcher(
+        PVector<Matcher<? super TypedNativeTypeDeclarationNode>> submatchers
+    ) {
+        super(submatchers);
+    }
+
+    @Override
+    protected Class<TypedNativeTypeDeclarationNode> expectedType() {
+        return TypedNativeTypeDeclarationNode.class;
+    }
+
+    @Override
+    protected TypedNativeTypeDeclarationNodeMatcher create(
+        PVector<Matcher<? super TypedNativeTypeDeclarationNode>> submatchers
+    ) {
+        return new TypedNativeTypeDeclarationNodeMatcher(submatchers);
+    }
+
+    public TypedNativeTypeDeclarationNodeMatcher withType(Matcher<? super SimpleNativeType> type) {
+        return with(has(
+            "typeOrConstructor",
+            x -> x.typeOrConstructor(),
+            isTypeNotConstructor(type)
+        ));
+    }
+
+    public TypedNativeTypeDeclarationNodeMatcher withTypeConstructor(Matcher<? super TypeConstructor<?>> type) {
+        return with(has(
+            "typeOrConstructor",
+            x -> x.typeOrConstructor(),
+            isConstructorNotType(type)
+        ));
+    }
+
+    public TypedNativeTypeDeclarationNodeMatcher withMethods(
+        Matcher<Iterable<? extends TypedNativeFunctionDeclarationNode>> methods
+    ) {
+        return with(has("methods", x -> x.methods(), methods));
+    }
+}
diff --git a/src/test/java/org/shedlang/compiler/ast/typed/TypedNodeMatchers.java b/src/test/java/org/shedlang/compiler/ast/typed/TypedNodeMatchers.java
index 7c0c4396..5d81d0f3 100644
--- a/src/test/java/org/shedlang/compiler/ast/typed/TypedNodeMatchers.java
+++ b/src/test/java/org/shedlang/compiler/ast/typed/TypedNodeMatchers.java
@@ -283,6 +283,10 @@ public class TypedNodeMatchers {
         return TypedNativeFunctionDeclarationNodeMatcher.empty();
     }
 
+    public static TypedNativeTypeDeclarationNodeMatcher isTypedNativeTypeDeclarationNode() {
+        return TypedNativeTypeDeclarationNodeMatcher.empty();
+    }
+
     public static Matcher<TypedParamNode> isTypedParamNode(
         String name,
         Matcher<Optional<? extends TypedTypeLevelExpressionNode<?>>> type
diff --git a/src/test/java/org/shedlang/compiler/typechecker/TypeCheckerNativeTypeDeclarationTests.java b/src/test/java/org/shedlang/compiler/typechecker/TypeCheckerNativeTypeDeclarationTests.java
new file mode 100644
index 00000000..c9dca725
--- /dev/null
+++ b/src/test/java/org/shedlang/compiler/typechecker/TypeCheckerNativeTypeDeclarationTests.java
@@ -0,0 +1,122 @@
+package org.shedlang.compiler.typechecker;
+
+import org.junit.jupiter.api.Test;
+import org.shedlang.compiler.ast.untyped.Untyped;
+import org.shedlang.compiler.ast.untyped.UntypedNativeTypeDeclarationNode;
+import org.shedlang.compiler.typechecker.errors.CannotDefineNativeTypeOutsideOfNamespaceError;
+import org.shedlang.compiler.types.NamespaceName;
+import org.shedlang.compiler.types.Types;
+
+import java.util.List;
+
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.shedlang.compiler.ast.typed.TypedNodeMatchers.isTypedNativeTypeDeclarationNode;
+import static org.shedlang.compiler.typechecker.TypeCheckerTesting.typeCheckNamespaceStatement;
+import static org.shedlang.compiler.types.TypeMatchers.*;
+import static org.zwobble.precisely.AssertThat.assertThat;
+import static org.zwobble.precisely.Matchers.*;
+
+public class TypeCheckerNativeTypeDeclarationTests {
+    private static final NamespaceName NAMESPACE_NAME = NamespaceName.of("Example");
+
+    @Test
+    public void whenOutsideOfNamespaceThenErrorIsThrown() {
+        var untyped = UntypedNativeTypeDeclarationNode.builder()
+            .withName("ExampleType")
+            .build();
+        var context = TypeCheckerContext.EMPTY;
+
+        assertThrows(
+            CannotDefineNativeTypeOutsideOfNamespaceError.class,
+            () -> TypeChecker.typeCheckStepsNamespaceStatement(untyped).typeCheckAllPhases(context)
+        );
+    }
+
+    @Test
+    public void whenDeclarationHasNoTypeLevelParamsThenTypedNodeHasSimpleNativeType() {
+        var untyped = UntypedNativeTypeDeclarationNode.builder()
+            .withName("ExampleType")
+            .build();
+        var context = TypeCheckerContext.EMPTY;
+
+        var typed = typeCheckNamespaceStatement(untyped, context);
+
+        assertThat(
+            typed.value(),
+            isTypedNativeTypeDeclarationNode()
+                .withType(isNativeType(NAMESPACE_NAME, "ExampleType"))
+        );
+    }
+
+    @Test
+    public void whenDeclarationHasTypeLevelParamsThenTypedNodeHasTypeConstructor() {
+        var untyped = UntypedNativeTypeDeclarationNode.builder()
+            .withName("ExampleType")
+            .withTypeLevelParams(List.of(
+                Untyped.typeParam("T1"),
+                Untyped.typeParam("T2")
+            ))
+            .build();
+        var context = TypeCheckerContext.EMPTY;
+
+        var typed = typeCheckNamespaceStatement(untyped, context);
+
+        assertThat(
+            typed.value(),
+            isTypedNativeTypeDeclarationNode()
+                .withTypeConstructor(isTypeConstructor(
+                    isSequence(
+                        isNativeTypeTypeLevelParam(NAMESPACE_NAME, "ExampleType", "T1"),
+                        isNativeTypeTypeLevelParam(NAMESPACE_NAME, "ExampleType", "T2")
+                    ),
+                    isNativeType(NAMESPACE_NAME, "ExampleType")
+                ))
+        );
+    }
+
+    @Test
+    public void whenDeclarationHasNoTypeParamsThenTypeIsAddedToEnvironment() {
+        var untyped = UntypedNativeTypeDeclarationNode.builder()
+            .withName("ExampleType")
+            .build();
+        var context = TypeCheckerContext.EMPTY;
+
+        var typed = typeCheckNamespaceStatement(untyped, context);
+
+        assertThat(
+            typed.context().compileTimeLookup("ExampleType"),
+            isOptionalOf(equalTo(Variable.defined(
+                Types.metaType(Types.nativeType(NAMESPACE_NAME, "ExampleType")),
+                VariableType.CONSTANT
+            )))
+        );
+    }
+
+    @Test
+    public void whenDeclarationHasTypeParamsThenTypeConstructorIsAddedToEnvironment() {
+        var untyped = UntypedNativeTypeDeclarationNode.builder()
+            .withName("ExampleType")
+            .withTypeLevelParams(List.of(
+                Untyped.typeParam("T1"),
+                Untyped.typeParam("T2")
+            ))
+            .build();
+        var context = TypeCheckerContext.EMPTY;
+
+        var typed = typeCheckNamespaceStatement(untyped, context);
+
+        assertThat(
+            typed.context().compileTimeLookup("ExampleType"),
+            isOptionalOf(allOf(
+                has("type", x -> x.type(), isOptionalOf(isTypeLevelValueType(isTypeConstructor(
+                    isSequence(
+                        isNativeTypeTypeLevelParam(NAMESPACE_NAME, "ExampleType", "T1"),
+                        isNativeTypeTypeLevelParam(NAMESPACE_NAME, "ExampleType", "T2")
+                    ),
+                    isNativeType(NAMESPACE_NAME, "ExampleType")
+                )))),
+                has("variableType", x -> x.variableType(), equalTo(VariableType.CONSTANT))
+            ))
+        );
+    }
+}
diff --git a/src/test/java/org/shedlang/compiler/types/TypeMatchers.java b/src/test/java/org/shedlang/compiler/types/TypeMatchers.java
index 2c777c76..c6480342 100644
--- a/src/test/java/org/shedlang/compiler/types/TypeMatchers.java
+++ b/src/test/java/org/shedlang/compiler/types/TypeMatchers.java
@@ -10,6 +10,14 @@ public class TypeMatchers {
     private TypeMatchers() {
     }
 
+    public static Matcher<TypeLevelValue> isNativeType(NamespaceName namespaceName, String name) {
+        return instanceOf(
+            SimpleNativeType.class,
+            has("namespaceName", x -> x.namespaceName(), equalTo(namespaceName)),
+            has("name", x -> x.name(), equalTo(name))
+        );
+    }
+
     public static Matcher<TypeLevelValue> isStructType(NamespaceName namespaceName, String name) {
         return instanceOf(
             SimpleStructType.class,
@@ -55,6 +63,21 @@ public class TypeMatchers {
         );
     }
 
+    public static Matcher<Type> isNativeTypeTypeLevelParam(
+        NamespaceName namespaceName,
+        String typeName,
+        String paramName
+    ) {
+        return instanceOf(
+            TypeParam.class,
+            has("scope", x -> x.scope(), instanceOf(
+                Scope.NativeType.class,
+                has("type", x -> x.type(), isNativeType(namespaceName, typeName))
+            )),
+            has("name", x -> x.name(), equalTo(paramName))
+        );
+    }
+
     public static Matcher<Type> isStructTypeLevelParam(
         NamespaceName namespaceName,
         String structName,